Apparatus for applying uniting band material to groups of rod-shaped articles



06L 1968 B. SCHUBERT 3,404,688

APPARATUS FOR APPLYING UNITING BAND MATERIAL TO GROUPS OF ROD-SHAPEDARTICLES Filed Dec. 15, 1965 2 Sheets-Sheet 1 INVENTOR. flarh 41rd flu.r

Oct. 8, 1968 APPARATUS FOR APPLYING UNITING BAND MATERIAL TO GROUPS OFROD-SHAPED ARTICLES Filed DEC. 15, 1965 NW MM 35a 125 1Z7H Fig.2 y F 403 47 3 4] 35a. y 29 15 v 35:: 3/

INVENTOR- B flu'alard @1010! Mane. 4m;

B SCHUBERT 3,404,689

2 SheetS STneet 2 United States Patent 3,404,689 APPARATUS FOR APPLYINGUNITING BAND MATERIAL TO GROUPS OF ROD-SHAPED ARTICLES BernhardSchubert, Hamburg-Lohbrugge, Germany, assignor t0 Hauni-Werke Korber &Co., K.G., Hamburg- Bergedorf, Germany Filed Dec. 15, 1965, Ser. No.514,019 Claims priority, application Great Britain, Dec. 17, 1964,51,466/64 14 Claims. (Cl. 131-21) ABSTRACT OF THE DISCLOSURE Apparatusfor joining tobacco rods with filter rod sections comprises a conveyorwhich advances groups of tobacco rods and filter rod sections past atransfer station where the groups are provided with patches ofadhesive-coated uniting band material fed by a rotary advancing device.The controls which regulate the feed of band material include a driveunit, a braking unit, a clutch which can connect the advancing devicewith the drive unit or with the braking unit, a detector which scans theconveyor for the presence or absence of groups, and an actuating devicewhich connects the advancing device with the braking unit when thedetector detects the absence of groups on the conveyor.

The present invention relates to apparatus for applying uniting bandmaterial to groups of rod-shaped articles. More particularly, theinvention relates to apparatus for applying patches of adhesive-coateduniting band material to groups of coaxial articles which may includetwo or more filter plugs or one or more filter plugs and one or moretobacco rods. For example, the apparatus of my invention may be resortedto for joining filter plugs of double unit length with pairs of coaxialcigarette rods of unit length to form filter cigarettes or double unitlength, or for joining two or more filter plugs into .a multiplex filterplug.

In filter cigarette machines, cigarette rods and filter plugs are joinedin rapid sequence by means of adhesivecoated patches which are obtainedon subdivision of a continuously advancing uniting band. The band isbeing withdrawn from a bobbin and one of its sides is coated withadhesive paste as it advances toward a transfer station where thepatches are applied to consecutive groups of aligned cigarettes andfilter plugs. Prior to reaching the transfer station, the band issubdivided into patches of requisite size, and such patches are appliedto consecutive groups by means of a rotary suction drum in a manner wellknown from the art of filter cigarette making. The feed for the unitinghand must be interrupted as soon as the feed of grouped rod-shapedarticles is interrupted for whatever reason, e.g., due to malfunction ofthe conveyor, because the patches might contaminate the machine or mightcause a complete breakdown if they are permitted to enter betweencertain moving parts.

It is already known to advance the uniting band by passing it betweentwo rollers one of which is driven to draw the band off the bobbin. Inthe event of an interruption in the feed of cigarette rods and/or filterplugs, one of the rollers is moved away from the other roller to therebyinterrupt the feed of band material. At the same time, the band isdisengaged from the paster and is gripped by a suitable braking deviceto positively prevent further advance of the band toward the transferstation. Reference may be had, for example, to US. Patent No. 3,081,778.However, it was found that the just outlined safety features cannotinsure sutficiently rapid interruption in the feed of uniting band,mainly because the Patented Oct. 8, 1968 aforementioned suction drumcontinues to rotate and tends to entrain the uniting band after theactual drive for the band is disengaged therefrom. in accordance with afurther proposal, the bearing for the bobbin on which the uniting bandis stored supports the bobbin with considerable friction so that theband is maintained under tension and is more likely to be arrestedwithout undue delay. A drawback of such constructions is that the bandis likely to tear because its material is rather weak.

Accordingly, it is an important object of the present invention toprovide an apparatus for controlling the feed of uniting band materialto a transfer station where patches of such band material are beingapplied to groups of travelling axially aligned rod-shaped articles andto provide the apparatus with means adapted to regulate the feed ofuniting band material in such a way that delays in the interruption offeed will develop only when such delays are actually desired.

Another object of the invention is to construct the apparatus in such away that the feed of uniting band material may be interrupted with aminimum of delay and without tearing or otherwise damaging the band.

A further object of the instant invention is to provide an apparatus forjoining groups of coaxial rod-shaped articles by patches ofadhesive-coated uniting band material and to construct the apparatus insuch a way that the feed of band material may be controlled by two ormore factors and that interruptions in the feed of band material may beaccompanied by automatic interruption in the feed of groups.

An additional object of the invention is to provide a novel clutch whichcontrols the operation of advancing means for uniting band material.

Briefly stated, one feature of my present invention resides in theprovision of an apparatus joining coaxial rod-shaped articles by meansof adhesive-coated uniting band material. The apparatus comprises meansfor feeding groups of coaxial articles sideways along a predeterminedpath and past a transfer station, means for feeding band material to thetransfer station, means for subdividing the moving material into patchesand for applying consecutive patches to successive groups at thetransfer station, means for scanning the path for the presence andabsence of groups, means for interrupting the feed of band material inresponse to detection of absence of such groups, and means for applyinga braking force to the advancing mechanism for the band materialsimultaneously with uncoupling of the advancing mechanism from itsdrive. If the path is scanned at a single point, such point may belocated upstream or downstream of the transfer station, preferablydownstream. However, it is also possible to scan the path both upstreamand downstream of the transfer station and to restart the feed foruniting band material only when the groups are detected at both scanningpoints.

In accordance with another feature of the invention, the feed of one ormore components of each group may be interrupted simultaneously with aninterruption in the feed of band material to prevent waste. For example,the components of each group may include one or more tobacco rods andone or more filter plugs or two or more filter plugs, depending uponwhether the apparatus is used in the production of filter cigarettes orcomposite (multiplex) filter plugs.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved apparatus itself, however, both as to its construction and itsmode of operation, together with additional features and advantagesthereof, will be best understood upon perusal of the following detaileddescription of certain specific embodiments with reference to theaccompanying drawings, in which:

FIG. 1 is a diagrammatic side elevational view of a filter cigarettemachine which embodies one form of the improved apparatus;

FIG. 2 is an enlarged fragmentary section substantially as seen in thedirection of arrows from the line IIlI of FIG. 1 and illustrates aclutch which is used to control the advancing means for uniting bandmaterial;

FIG. 3 is a circuit diagram showing a portion of a modified apparatus;and 1 FIG. 4 is a fragmentary side elevational view of a filter machinewhich embodies a different apparatus.

Referring first to FIGS. 1 and 2, there is shown a filter cigarettemachine wherein two types of rod-shaped articles, namely, pairs ofcoaxial cigarette rods 3 of unit length and filter plugs 6 of doubleunit length, are joined by an apparatus which wraps patches '11 ofadhesivecoated uniting band material 14 around the filter plugs 6 andaroundthe adjoining end portions of the cigarette rods 3. The apparatuscomprises a conveyor including two cooperating rotary drums 4 and 9which advance groups 8 (each composed of two coaxial cigarette rods 3and a filter plug 6 therebetween) toward, past and beyond a transferstation which is adjacent to a portion of the second drum 9. The feedfor supplying pairs of coaxial but spaced cigarette rods 3 intoconsecutive pockets or holders 4a of the drum 4 comprises an inclinedchute 2 and a rotary transfer drum 1. The drum 1 is also provided withaxially parallel pockets or holders 1a and is partially surrounded byone or more arcuate shields 1b which retain the cigarette rods 3 duringtravel to the point of transfer between the drums 1 and 4. Similarshields 4b and 9b surround portions of the drums 4 and 9. The feed forfilter plugs 6 comprises an inclined chute 7 and a rotary drum 5 havingaxially parallel pockets 5a and cooperating with arcuate retainingshields 5b. The arrangement is such that the pockets 5a discharge filterplugs '6 into gaps between pairs of cigarette rods 3 in the pockets 4aof the drum 4. The thus obtained groups 8 are then conveyed betweeninclined condensing or shifting cams 40 which cause the cigarette rods 3to move axially toward the adjoining ends of the aligned filter plugs.The groups 8 are then transferred into consecutive pockets 9a of thedrum 9 and travel along the shields 95 toward and past the transferstation 10.

The aforementioned apparatus further comprises a bobbin 17 or a similarsource of uniting band material, advancing means for withdrawing suchmaterial from the bobbin 17, and a novel control assembly for regulatingthe feed of band material to the transfer station 10. The advancingmeans includes a driven advancing roller and an idler roller 16. The web14 of uniting band material is guided through the gap 'between therollers 15, 16 and is being paid out by the bobbin 17 as long as theroller 15 rotates. The underside of the Web 14 is then guided along apaster roller 18 of conventional design which coats the web with a filmof adhesive. The roller 18 receives adhesive from an intermediate roller18a which dips into a supply of adhesive contained in a paste pot 18b.The thus coated web is then guided around a revolving suction drum 12which serves as a means for applying patches 11 to consecutive groups 8.The patches 11 are formed by a revolving knife 13 which cooperates withthe suction drum 12 and severs the web 14 at regular intervals, Therollers 15, 16 move the web 14 at a speed which is somewhat less thanthe peripheral speed of the suction drum 12 so that each freshly severedpatch 11 moves away from the leading end of the remainder of the web 14to insure unobstructed transfer to the respective group 8.

Each group 8 which has advanced past the transfer station 10 carries apatch 11, and such patches may extend substantially tangentially of therespective filter plugs 6.

The groups are then advanced along-arcuate shields 9c and aretransferred into consecutive pockets 19a of a rotary wrapping drum 19surrounded by a shield 1%. While travelling with the drum 19, thepatches-11 are convoluted aroundthe respective filter plugsv 6 andaround the adjoining end portions of the cigarette-rods 3 to. betransformed into tubes which serve to connect the cigarette rods. withthe respective filter plugs and to transform each group 8 into a filtercigarette 20 of double unit length. Such cigarettes 20 are thereupontransferred into consecutive pockets 21a of a so-called cutting drum 21which is surrounded by shields 21b and advances the cigarettes past arapidly revolving disk-shaped cutter 22 so thatthe cigarettes 20 aresevered in planes extending midway across the convoluted patches 11 andyield pairs of filter cigarettes 23 ofdouble unit length. The cigarettes23 are deposited onto the upper-stringer of a transporting belt 24 whichadvances them to storage, to a station where the cigarettes aretransferred into trays, or directly to a packing machine.

With the exception of the advancing means 15, 16 and of theaforementioned control assembly, the heretofore described components ofthe filter cigarette machine are well known in the art and by themselvesform no part of my present invention.

The invention resides mainly in the provision of the control assemblyand in the manner in which the control assembly may regulatevthe feed ofuniting band material and, if desired, the feed of cigarette rods 3and/or filter plugs 6. This control assembly includes a drive unit forthe roller 15, a braking unit 41, a clutch '35 which can couple theroller 15 with the drive unit or with the braking unit (but not withboth units at the same time), a detector assembly including twodetecting or scanning members 25, 27 and an actuating assembly includingtwo electric switches 26, 28 and a solenoid 29. The actuating assemblyserves to uncouple the clutch 35 from the drive unit or from the brakingunit, depending upon whether or not one of the scanning members 25, 27has detected the presenceor absence of assemblies 8 on the conveyorwhich includes thedrums 4 and 9. The scanning member constitutes a tripfor the switch 25 which is-normally open, and the scanning member 27'constitutes'a trip for the normally open switch 28. These switches areconnected in parallel and their circuit further includes a suitablesource 30a of electrical energy. A first conductor 30 connects one poleof the source 30a with the solenoid 29; a second conductor 31 connectsthe solenoid with one contact of the switch 28; a third conductor 33connects this one contact of the switch 28 with one contact of theswitch 26; a fourth conductor 34 connects the other contact of theswitch 26.with.the other contact of the switch 28; and a fifth conductor32 connects the other contact of the switch 28 withthe otherpole of thesource 30a. The trip 25 is adjacent to theperiphery of .the drum 4,i.e., it is located upstream of the transfer station 10 and is arrangedto scan the drum 4 for the presence or absence of entire groups 8 or forthe presence or absence of one or two r0d-shaped components of suchgroups. In other words, the trip 25 may detect that an entire group 8 ismissing, that a pocket 4a contains only one or two cigarette rods 3, orthat a pocket 4a contains only a filter plug 6 or a filter plug and asingle cigarette rod. The length of the trips 25 and 27 is such thateach thereof can overlie two adjacent pockets 4a or 9a at a time. InFIG. 1 the trip 25 is shown in its lower end position because itoverlies two empty pockets 4a. Therefore, the switch 26 is closed andthe solenoid 29 is energized. The switch 28 is open because thecorresponding trip 27 overlies two filled pockets 9a; nevertheless, thesolenoid 29 remains energized because the switches 26 and 28 areconnected in parallel. If the trip 25 and switch 26 were installed inthe zone between the transfer drums 1 and 5, the trip 25 could onlydetect the presence or absence of one or both cigarette rods 3. When thefilter cigarette machine operates properly, the trips 25 and 27 arelifted by the groups 8 which advance therebelow so that the circuit ofthe switches 26, 28 is open and the solenoid 29 is deenergized. The trip27 and the switch 28 are located downstream of the transfer station sothat the trip 27 can detect the presence or absence of groups 8 whichare already provided with patches 11.

The solenoid 29 comprises a reciprocable armature 29a (see FIG. 2) whichcan move the dog 35a of the clutch 35 to a first end position. The dog35a is biased by a spring 35c which tends to move it to a second endposition. When the solenoid 29 is energized, it expels the armature 29a(i.e., the armature then moves in a direction to the left, as viewed inFIG. 2), so that the dog 35a is rocked against the bias of the spring35c and is disengaged from the teeth of a clutch element 35d. One arm ofthe dog 35a then bears against an internal braking surface 41' providedon the stationary braking unit 41. As shown, the dog 35a resembles atwo-armed lever and is mounted on a pivot pin 35:: carried by a clutchelement 35b atfixed to the shaft 36 of the driven advancing roller 15.The clutch element 3501 is rigid or integral with a pinion 37 whichforms part of the drive unit for the roller 15, this drive unit furtherincluding a gear 38 which meshes with the pinion 37, a pinion 39 whichis coaxially secured to the gear 38, and a further gear 40 which drivesthe pinion 39. The drive unit, the shaft 36 of the roller 15, and theshaft 16a of the idler roller 16 are mounted on a plate-like framemember F which preferably supports the entire filter cigarette machine.The gear 40 is driven by a suitable transmission from the main driveshaft of the machine or directly by an electric motor, not shown. Thepinion 37 and the clutch element 35d are rotatable with reference to theroller shaft 36.

The operation of the filter cigarette machine is as follows:

If there is an interruption in the feed of cigarette rods 3 and/ orfilter plugs 6, the trip 25 descends to the position of FIG. 1 as soonas it is bypassed by the last complete group 8 whereby the switch 26closes and the solenoid 29 is energized. The armature 29a is expelledand rocks the dog 35a to the position of FIG. 2 whereby the dogdisengages the clutch element 35b from the clutch element 35d (i.e., itdisconnects the roller 15 from the drive unit) and simultaneouslycouples the roller 15 with the braking unit 41 by bearing against thestationary braking surface 41. This brings the roller 15 to an immediatehalt, together with the web 14 so that the suction drum 12 cannot applypatches 11 to the groups 8.

The suction prevailing in the interior of the drum 12 is selected insuch a way that the leading end of the web 14 adheres to the peripheryof the drum but cannot tear it the drum 12 continues to rotate after theroller 15 is brought to a standstill. In other words, and if the suctiondrum 12 continues to rotate after the roller 15 is arrested, theslippage between the web 14 and the drum 12 simply increases but the webremains intact. The magnitude of the force produced by the drum 12 whichtends to move the web 14 lengthwise may be regulated by changing thearea of contact between the periphery of this drum and the web.

The apparatus of my invention may be further provided with a devicewhich lifts the web 14 away from the paster roller 18 as soon as thesolenoid 29 is energized. For example, such a device may comprise alifting roller which is mounted in the zone between the rollers 15 and18 and moves upwardly as soon as the circuit of the solenoid 29 iscompleted, either by receiving motion directly from the armature 29a orfrom the armature of a second solenoid which is connected in series withthe solenoid 29. The web 14 remains disengage-d from the roller 18 untilthe dog 35a reestablishes the driving connection between the pinion 37and the shaft 36.

If the disturbance in the feed of cigarette rods 3 and/ or filter plugs6 is eliminated and a freshly assembled group 8 again lifts the trip 25,the latter opens the switch 26 so that the solenoid 29 is deenergizedand retracts the armature 29a whereby the spring 350 is free to rock thedog 35a back into engagement with the teeth of the clutch element 35d tocouple the drive unit with the advancing roller 15. Of course, suchdeenergization of the solenoid 29 can take place only if the switch 28is also open. However, the switch 28 can open only after a fresh row ofgroups reaches the second trip 27 so that the solenoid 29 remains inenergized condition despite the fact that the switch 26 might be opendue to the presence of groups 8 in the space below the trip 25. In otherwords, the roller 15 will begin to feed the web 14 only when acontinuous row of groups 8 extends all the way from the trip 25 to thetrip 27 so that these trips open the switches 26 and 28..

As stated before, the trips 25 and 27 may be constructed andconfigurated in such a way that each thereof can detect the presence ofone, two or all three rod-shaped components of a group 8. For example,each of these trips may comprise three fingers each of which can scanthe drum 4 or 9 for the presence of a single cigarette or filter plug.Each finger can by itself open or close the corresponding switch 26 or28.

While it would .be possible to omit one of the trips 25, 27, theactuating assembly which includes two trips is preferred for thefollowing reasons. If the apparatus of FIG. 1 were without the trip 25,the trip 27 could detect the absence of groups 8 only at a time when atleast one patch 11 was already transferred to the drum 9 without meetinga group of cigarette rods and filter plugs. In other words, such patchor patches could contaminate the machine. In the absence of the trip 27,the roller 15 would begin to feed the web 14 as soon as the trip 25would detect a group 8 whereby the suction drum 12 would again transferpatches 11 to a series of empty pockets before the patches would beginto meet properly assembled groups of filter plugs and cigarette rods. Inother words, by using two trips which are respectively disposed upstreamand downstream of the transfer station 10, I insure that the patches 11cannot be applied to the drum 9. However, it is equally within thepurview of my invention to omit one of the trips 25, 27 and to controlthe feed of uniting band material by a single detecting member which maybe installed upstream or downstream of the transfer station. If the trip25 is used alone, the circuit of the sole noid 29 preferably includes asuitable time-lag relay which delays the coupling of the shaft 36 withthe pinion 37 for an interval of time which suffices to insure that theforemost group 8 at least reaches the transfer station 10 when the drum12 begins to apply patches 11.

It is often desirable to interrupt the feed of filter plugs 6 and/ orcigarette rods 3 simultaneously with an interruption in the feed ofuniting band material. For example, the filter cigarette machine of FIG.1 may be provided with a clutch which disengages the transfer roller 5from its drive simultaneously with energization of the solenoid 29 sothat the operator may eliminate a disturbance in the feed of filterplugs 6. In the absence of such a clutch, all of the filter plugs 6which would be fed subsequent to a disturbance in the feed of cigaretterods 3 would go to waste and could eventually clog up the machine. Asindicated in FIG. 1 by phantom lines, the switch 26 may constitute adouble-pole switch which is connected with conductors 69, 70 formingpart of an actuating assembly for a clutch serving to couple the shaft5d of the transfer drum 5 with a drive unit or with a braking unit. FIG.1 merely indicates a solenoid 71 which may be energized when the switch26 is allowed to close in response to detection of the absence of agroup 8 or of cigarette rods 3 so as to effect an immediate brakingaction upon the shaft 5 and to prevent further feed of filter plugs 6.

FIG. 3 illustrates a modified actuating device for the clutch 35. Thisactuating device comprises a solenoid 129 having a reciprocable armature129a, and two electric switches 126, 128 which are connected in series.These switches are normally biased to closed positions but may be openedby two trips 125, 127 which correspond to the trips 25, 27. The solenoid129 is normally energized and then retracts the armature 129a so thatthe dog a of the clutch 35 can couple the drive unit with the roller 15.When one of the trips 125, 127 detects the absence of a group 8, itopens the respective switch 126 or 128 so that the solenoid isdeenergized whereby a spring 12911 expels the armature 129a and thelatter causes the dog 35a to couple the roller 15 with the braking unit41.

Referring finally to FIG. 4, there is shown a machine for the productionof so-called multiplex filters, i.e., for the production of compositefilters which consist of two or more different filter materials. Thismachine again comprises a conveyor including two cooperating drums 51,54 which transport groups 52 of coaxial filter rod sections past atransfer station 56 which is adjacent to the drum. 54. The pockets ofthe drum 51 receive such groups from a feed which includes four coaxialtransfer drums 46, 47, 48, 49 which respectively cooperate with chutes42, 43, 44 and 45. Each chute supplies to the respective transfer drum adifferent filter plug 50 of unit length or multiple unit length.

The width of the web 59 is such that patches 57 of this Web may beconvoluted around all of the filter plugs 50 which form a group 52. Thegroups 52 which have advanced past the transfer station 56 and areprovided with patches 57 are then transferred into the pockets of awrapping drum 63 which completes the wrapping of patches around therespective groups 52 and transforms each such group into a multiplexfilter rod 64.

The web 59 is being withdrawn from a suitable bobbin (not shown) bymeans of an advancing unit including a driven roller 60 and an idlerroller 61. The underside of the Web 59 is coated with adhesive by apaster roller 62 and the web is then guided around a suction drum whichcooperates with a revolving knife 58 to form the patches 57.

The advancing roller may be coupled with a drive unit or with a brakingunit in the same way as shown in FIG. 2. FIG. 4 merely shows theactuating device and the detector which latter includes a single trip 53adjacent to the drum 51, i.e., upstream of the transfer station 56. Thistrip 53 controls an electric switch which forms part of the actuatingdevice and is connected in circuit with a solenoid 68 by means ofconductors 66, 67. The circuit further includes a source 66a ofelectrical energy. The wrapping drum 63 delivers the filter rods 64 to acutting drum, to storage or directly to a filter cigarette machinewherein the rods 64 may be severed to yield filter plugs or desiredlength.

If the trip 53 detects the absence of a single group 52 or of two ormore groups, it moves to the lower end position shown in FIG. 4 andcauses the switch 65 to close so as to energize the solenoid 68 wherebythe armature of the solenoid causes the clutch (not shown) to couple theroller 60 with the braking unit. The circuit of the solenoid 68 includesa suitable time-lag relay which serves to delay the energization of thesolenoid for an interval of time which suffices to insure that all ofthe groups which happen to be located between the trip 53 and thesuction drum 55 will advance beyond the transfer station 56 before thefeed of the web 59 is interrupted. The relay 75 further insures that,when the trip 53 is lifted in response to detection of a fresh group52', the solenoid 68 is de-energized with such a delay that the group 52can reach the transfer station 56 at the time when the suction drum 55transfers the foremost patch 57. In other words, the function of therelay 75 is to insure that the suction drum 55 will transfer patches 57only and alone at such times when the groups 52 actually travel past thetransfer station 56.

A very important feature of my improved apparatus is believed to residein that the web 14 or 59 need not be directly subjected to the action ofa braking device.

Thus, instead of directly braking the web, I prefer to apply a brakingaction to the advancing roller 15 or 60. This roller need not be swungto and from the idler roller 16 or 61 so that the feed for the unitingband material is of rather simple and rugged design. The braking actionupon the roller 15 or 60 can begin simultaneously with an interruptionof driving connection between the driving unit and the roller 15 or 60so that full braking action can be applied practically without anydelay. It was found that such application of the braking force resultsin more rapid interruption in the feed of uniting band material. Theclutch 35 is a very simple device which can be readily installed inpresently known filter machines or filter cigarette machines withoutnecessitating any appreciable alterations in the mounting and/oroperation of the remaining parts.

While it is possible to connect the clutch 35 and the detecting members25, 27 or 53 by means of more complicated (mechanical or pneumatic)actuating assemblies, an electrical actuating assembly which includesthe solenoid 29, 129 or 68 has been found to be particularly suitedbecause it can transmit signals or impulses without delay and is muchless prone to malfunction than a mechanical or pneumatic device.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of my contribution to the art and, therefore, suchadaptations should and are intended to be comprehended Within themeaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is:

1. An apparatus for joining coaxial rod-shaped articles by uniting bandmaterial, particularly for joining tobacco rods and/or filter plugs,comprising conveyor means for feeding groups of rod-shaped articles pasta transfer station; a source of uniting band material; rotary advancingmeans for feeding such material from said source to said transferstation; and control means for regulating the feed of band materialincluding a drive unit and a braking unit for said advancing means,clutch means for coupling said advancing means with one of said units ata time, detector means for scanning said conveyor means for the presenceand absence of groups, and actuating means connecting said detectormeans with said clutch means so as to couple said advancing means withsaid braking unit in response to the absence of groups on said conveyormeans.

2. An apparatus as set forth in claim 1, wherein said clutch meanscomprises a dog movable by said actuating means between first and secondpositions in which said advancing means is respectively coupled withsaid drive unit and said braking unit.

3. An apparatus as set forth in claim 2, wherein said braking unitcomprises a fixed braking surface and wherein said dog engages saidbraking surface in the respective position thereof to thereby hold saidadvancing means against rotation.

4. An apparatus as set forth in claim 1, wherein said actuating meanscomprises a solenoid having a movable armature which controls saidclutch means.

5. An apparatus as set forth in claim 1, wherein said detector meanscomprises a detecting member which is *located upstream of said transferstation.

6. An apparatus as set forth in claim 1, wherein said detector meanscomprises a detecting member which is located downstream of saidtransfer station.

7. An apparatus as set forth in claim 1, wherein said detector meanscomprises two detecting members which are respectively located upstreamand downstream of said transfer station.

8. An apparatus as set forth in claim 7 wherein said actuating means isarranged to couple said advancing means with said braking unit when atleast one of said detecting members detects the absence of groups onsaid conveyor means.

9. An apparatus as set forth in claim 1, wherein said actuating meanscomprises an electric switch which is movable between open and closedpositions and normally assumes one of said positions, said detectormeans comprising a trip which moves said switch to the other position inresponse to detecton of the absence of groups on said conveyor means.

10. An apparatus as set forth in claim 1, further comprising a feed forsupplying rod-shaped articles to said conveyor means upstream of saidtransfer station and means for arresting said feed in response todetection of the absence of groups by said detector means.

11. An apparatus as set forth in claim 1, wherein said actuating meanscomprises two electric switches each of which is movable between openand closed positions and normally assumes one of said positions, saiddetector means comprising two trips respectively located upstream anddownstream of said transfer station and each arranged to move thecorresponding switch to the other position upon detection of the absenceof groups on said conveyor means, sai-d clutch means being arranged tocouple said advancing means with said braking unit when at least one ofsaid switches is moved to said other position.

12. An apparatus as set forth in claim 11, wherein each of said switchesis open in said one position thereof and wherein said switches areconnected in parallel, said actuating means comprising a solenoidconnected in circuit with said switches and having a movable armaturewhich operates said clutch means to couple said advancing means withsaid braking unit when said circuit is completed across at least one ofsaid switches to energize said solenoid.

13. An apparatus as set forth in claim 11, wherein each of said switchesislclosed in said one position thereof and wherein said switches areconnected in series, said actuating means further comprising a solenoidconnected in circuit with said switches and having a movable armaturewhich operates said clutch means to couple said advancing means withsaid braking unit when at least one of said switches is open to thusdeenergize said solenoid.

14. An apparatus as set forth in claim 1, wherein said actuating meanscomprises a delay device arranged to effect coupling of said advancingmeans with said drive unit with a delay following detection of groups bysaid detector means and to elfect coupling of said advancing means withsaid braking unit with a delay following detection of the absence ofgroups on said conveyor means, said detector means comprising adetecting member located upstream of said transfer station and saiddelays being of such duration that a group detected by said detectingmember reaches the transfer station when said advancing means is coupledto said drive unit and that the last group preceding detection of theabsence of groups on said conveyor means reaches the transfer stationprior to interruption of feed by said advancing means.

References Cited UNITED STATES PATENTS 3,212,507 10/1965 Schubert 131-213,233,613 2/1966 Korber et al 131-20 3,308,833 3/1967 Dearsley 131-943,306,306 2/ 1967 R udszinat 131-94 HUGH R. CHAMBLEE, Primary Examiner.

